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How to test a portable generator

How to test a portable generator

Having the use of a portable diesel generator can be crucial – and so often the need to use it comes around instantly, without much notice. However, if the generator hasn’t been used for a while, there’s an increased chance that the generator won’t be able to start up, which of course isn’t ideal if it’s required to provide back-up power in an emergency.

Fortunately, the experienced team members at Vital Power have worked within the generator industry for many years, so we know a thing or two about diesel generators. So, we put together this guide covering a few tips and suggestions on what to do if your portable or diesel generator won’t start, and how to test a portable generator.

How do you test a portable generator?

Check generator fuel

Fuel is, perhaps unsurprisingly, one of the main and most common generator problems. So, it’s always best to double-check that there is sufficient fuel available. It may simply need refuelling with additional diesel to get up and running.

However, if the current load of fuel has been sitting in the generator for a considerable amount of time, then it may be best to remove and replace to avoid any issues from occurring. At Vital Power we offer fuel polishing to make sure your generator is running on top quality fuel.

Test generator battery

Just a with a car battery, the battery within a generator can also run flat or lose power. This is why it may need testing before you attempt to start up to make sure you’ll get the power output you need.

Using a multimeter will help you gain a better idea of the quality of the battery, but you will need another power source to boost up the battery for usage. To make sure your battery is in good condition, it’s important to have regular generator maintenance services.

Clean the generator air filter

For the generator to operate smoothly, it’s important that the filter is clean and clear at all times. Debris, clogs and rust can all get in the air filter and cause dangerous blocks.

The generator air cleaner can easily be pulled out and cleaned, although new air filters are also simple and affordable to purchase if needed.

Check the generator carburettor

The generator carburettor is also a key component that needs to be investigated and cleaned. As old diesel fuel slowly becomes sticky and thick, it can easily clog the carburettor, preventing the generator from being able to start. Check our generator parts diagram for more insight into all the generator parts you’ll need to keep clean.

Why you need to test portable and diesel generators

Though diesel generators are generally reliable sources of standby power that any business can rely on, there are a few potential problems you’ll need to keep an eye out for to make sure your generator is ready at a moment’s notice.

Familiarise yourself with the most common generator problems, and keep an eye out for the below issues (that can be helped with regular tests)…

Generator battery failure

As well as running out of fuel, battery failure is often one of the more common reasons the generator isn’t starting. Like most batteries in machinery, it’s very easy for the connection between the components to become loose or disconnected, though fortunately this generally isn’t too much of a problem to repair.

On average, you should be replacing your generator’s batteries every two to three years, though this depends on the age of the generator, how often it’s used and the generator’s recommended guidebook.

Generator fuel quality

The quality of generator diesel fuel is often one of the primary suspects if a generator isn’t starting. Some of the most common issues that aren’t necessarily noticeable to the naked eye include impurities in the fuel, clogged air intake and too much or too little supply of fuel to the combustion chamber.

We recommend booking fuel quality testing with our team of engineers to make sure you’re using fuel that’s up to scratch.

Generator liquid level low

Just as with fuel, your generator may also be running low on various other essential liquids. Two of the most notable shortages that can cause the generator to not start-up include the coolant and oil. Not having enough of either of these generator liquids can cause serious damage to the engine, so make sure they are filled adequately during the starting up process.

Check out our Vital Power generator troubleshooting guide for more help with getting your generator to start.

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